Biochar amendment of landfill clay liner soil & leachate

Published 07-12-2023
Section Research Articles


  • Aparna P S Vidya Academy of Science and Technology, Thrissur, India
  • Arunima K M Vidya Academy of Science and Technology, Thrissur, India
  • Devika M V Vidya Academy of Science and Technology, Thrissur, India
  • Seetha Pissharikkel Vidya Academy of Science and Technology, Thrissur, India


Landfill, compacted clay, leachate, biochar, optimum dosage


The biodegradable wastes from the households collected have to be properly applied to municipal solid waste landfills. Landfills usually have liner systems and other safeguards to prevent contamination of the surroundings and the groundwater. There are various types of bottom liner systems, the simplest type being usually compacted clay. The clay has some unique character of low permeability, which is the main reason to use clay as the liner. If the compacted clay liners kept for their function, are not properly executed, there can be chances of leachate movement through it, to percolate to underground water systems. In this work, the experimental study of the addition of biochar with proposed samples of clay liner system & synthesized leachate was studied. From literature review, it was found out that the minimum dosage of biochar was 3% and that the biochar was made by burning sunflower husks. Biochar treatment of leachate alters not only the turbidity but also the nitrogen, chloride, and phosphate content. Biochar is also used as a coagulant in many water treatment plants. The representative clay soil samples were collected from Manali river beds and laboratory permeability tests were conducted with a soil-biochar mixture for the varied dosages 0.5, 1, 1.5, 2, 2.5 and 3. Similarly, municipal solid waste was laid with clay and thus synthesized leachate was
amended with similar dosages of biochar 0.5, 1, 1.5, 2 and 2.5. The percentage of biochar addition corresponding to which soil biochar mix yielded minimum permeability was noted at 2% & the leachatebiochar dispersion showed the minimum level of turbidity was investigated also at 2%. Therefore, the paper is the outcome of an attempt to determine the optimum dosage of biochar to clay liner soil to improve the properties concerning permeability and to find out the range of biochar addition with leachate to lessen the anticipated level of contamination to subsurface water.